title: Lumpectomy and radiation therapy for the treatment of intraductal breast cancer: findings from National Surgical Adjuvant Breast and Bowel Project B-17.
abstract: OBJECTIVE
  In 1993, findings from a National Surgical Adjuvant Breast and Bowel Project (NSABP) trial to evaluate the worth of radiation therapy after lumpectomy concluded that the combination was more beneficial than lumpectomy alone for localized intraductal carcinoma-in-situ (DCIS). This report extends those findings.
  
  
  METHODS
  Women (N = 818) with localized DCIS were randomly assigned to lumpectomy or lumpectomy plus radiation (50 Gy). Tissue was removed so that resected specimen margins were histologically tumor-free. Mean follow-up time was 90 months (range, 67 to 130). Size and method of tumor detection were determined by central clinical, mammographic, and pathologic assessment. Life-table estimates of event-free survival and survival, average annual rates of occurrence for specific events, relative risks for event-specific end points, and cumulative probability of specific events comprising event-free survival are presented.
  
  
  RESULTS
  The benefit of lumpectomy plus radiation was virtually unchanged between 5 and 8 years of follow-up and was due to a reduction in invasive and noninvasive ipsilateral breast tumors (IBTs). Incidence of locoregional and distant events remained similar in both treatment groups; deaths were only infrequently related to breast cancer. Incidence of noninvasive IBT was reduced from 13.4% to 8.2% (P = .007), and of invasive IBT, from 13.4% to 3.9% (P < .0001). All cohorts benefited from radiation regardless of clinical or mammographic tumor characteristics.
  
  
  CONCLUSIONS
  Through 8 years of follow-up, our findings continue to indicate that lumpectomy plus radiation is more beneficial than lumpectomy alone for women with localized, mammographically detected DCIS. When evaluated according to the mammographic characteristics of their DCIS, all groups benefited from radiation.
authors.affiliation: National Surgical Adjuvant Breast and Bowel Project Operations and Statistical Centers, USA.
authors.forename: B
authors.initials: B
authors.lastname: Fisher
authors.forename: J
authors.initials: J
authors.lastname: Dignam
authors.forename: N
authors.initials: N
authors.lastname: Wolmark
authors.forename: E
authors.initials: E
authors.lastname: Mamounas
authors.forename: J
authors.initials: J
authors.lastname: Costantino
authors.forename: W
authors.initials: W
authors.lastname: Poller
authors.forename: E R
authors.initials: ER
authors.lastname: Fisher
authors.forename: D L
authors.initials: DL
authors.lastname: Wickerham
authors.forename: M
authors.initials: M
authors.lastname: Deutsch
authors.forename: R
authors.initials: R
authors.lastname: Margolese
authors.forename: N
authors.initials: N
authors.lastname: Dimitrov
authors.forename: M
authors.initials: M
authors.lastname: Kavanah
mesh_terms: D001943:Breast Neoplasms / Q000401:mortality / Q000532:radiotherapy / Q000628:therapy*; D002278:Carcinoma in Situ / Q000401:mortality / Q000532:radiotherapy / Q000628:therapy*; D018270:Carcinoma, Ductal, Breast / Q000401:mortality / Q000532:radiotherapy / Q000628:therapy*; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D015996:Survival Rate